Jurnal Alotrop ber ISSN 2252-8075 adalah majalah ilmiah resmi yang diterbitkan oleh Program Studi Pendidikan Kimia Jurusan Pendidikan MIPA Fakultas Keguruan dan Ilmu Pendidikan Universitas Bengkulu, sebagai sumbangannya kepada pengembangan Ilmu Kimia dan Pendidikan Kimia yang diterbitkan dalam Bahasa Indonesia yang memuat hasil-hasil penelitian, telaah/tinjauan pustaka, kasus lapangan atau gagasan dalam bidang ilmu Kimia dan Pendidikan Kimia
[ANTIXOXIDANT AND ANTIBACTERIA ACTIVITIES OF Strobilanthes crispus Bl (Keji Beling) EXTRACT AGAIN... more [ANTIXOXIDANT AND ANTIBACTERIA ACTIVITIES OF Strobilanthes crispus Bl (Keji Beling) EXTRACT AGAINST Stapylococcus Aureus AND Escherichia coli] Strobilanthes crispus Bl (Keji Beling) is one of herbs that has been used for the treatment of several types of diseases such as kidney stones, gall stones, diabetes, cholesterol, tumors and others. The purpose of this study was to determine the value of antioxidant activity (IC 50) and antibacterial activity of ethanol extract of leaf vermicelli against Staphylococcus aureus and Escherichia coli bacteria. Antioxidant test was performed using DPPH method and vitamin C was used as standard. While the antibacterial activity test done by paper disc method. Amphicillin is used as a positive control and aquades as a negative control. Ethanol extract of leaf vermicelli able to counteract free radical of DPPH with IC 50 value that is: 102.85 ppm and IC 50 value from vitamin C as comparative solution equal to 19.268 ppm. The results of antibacterial inhibition test of ethanol extract of vile leaf on S. aureus bacteria with extract concentration of 20% (0 mm), 40% (2.5 mm), 60% (3.25 mm), and 80% (4.75) were included Weak and 100% (5.75 mm) including Medium, and E.coli antibacterial inhibition in the extract contacts of 20% (0 mm), 40% (2 mm), 60% (2.25 mm), 80% (4.25 mm) were weak, and 100% (5.25 mm) including moderate. So it is known that the extract of ethanol leaves vile at 100% concentration can inhibit the growth of S. aureus bacteria and E. coli bacteria characterized by the formation of the largest clear zone diameter at the concentration. But the strength of its bacteria is still not effective to inhibit the growth of both test bacteria. Abstrak Strobilanthes crispus Bl (Keji Beling) merupakan salah satu tanaman herbal yang telah digunakan untuk pengobatan beberapa jenis penyakit antara lain batu ginjal, batu empedu, diabetes, kolesterol, tumor dan lain-lain. Tujuan dari penelitian ini adalah untuk menentukan nilai aktivitas antioksidan(IC 50) dan aktivitas antibakteri dari ekstrak etanol daun Strobilanthes crispus Bl terhadap bakteri Staphylococcus aureus dan Escherichia coli. Uji antioksidan dilakukan menggunakan metoda DPPH dengan vitamin C sebagai standar, dan uji aktivitas antibakteri dilakukan dengan metoda kertas cakram menggunakan Amphisilin sebagai kontrol positif dan aquades sebagai kontrol negatif. Ekstrak etanol daun S. crispus Bl mampu menangkal radikal bebas DPPH dengan nilai IC 50 yaitu: 102.85 ppm dan nilai IC 50 dari vitamin C sebagai larutan pembanding sebesar 19.268 ppm. Hasil uji daya hambat antibakteri ekstrak etanol daun S.crispus Bl pada bakteri S. aureus dengan konsentrasi ekstrak 20% (0 mm)
[COMPARISON FROM LEARNING OUTCOMES OF PROBLEM BASED LEARNING MODELS AND THINK TALK WRITE MODELS ]... more [COMPARISON FROM LEARNING OUTCOMES OF PROBLEM BASED LEARNING MODELS AND THINK TALK WRITE MODELS ] Each learning model has advantages and disadvantages in every process.This research intent to know the difference student studying result on chemical learning among brazes that utilize learning model Problem Based Learning (PBL) with class that utilize learning model Think is Write's Talc (TTW) on jurisdictional material – chemical base law at class X SMA Negeri 10 Kota Bengkulu's. This research constitute quasi's experiment. Students learned result on observational it is seen from pretest's point and posttest difference. On class that utilize Problem Based Learning (PBL) model , increasing average value from student kognitiv as big as 49,23. Meanwhile class that utilize Think is Write's Talc (TTW) model , increasing average value learned student kognitiv as big as 56,33. Hypothese was tested by use of t test (α = 0,01) to result at t test = 3,53 < t table = 2,38. Research result to point out that are distinctive result that significan among between class that utilize Problem Based Learning (PBL) model and class that utilize Think is Write's Talk (TTW) model. Abstrak Penelitian ini bertujuan untuk mengetahui perbedaan hasil belajar siswa pada pembelajaran kimia antara kelas yang menggunakan model pembelajaran Problem Based Learning (PBL) dengan kelas yang menggunakan model pembelajaran Think Talk Write (TTW) pada materi hukum – hukum dasar kimia di kelas X SMA Negeri 10 Kota Bengkulu Tahuyn ajaran 2016/2017. Penelitian ini merupakan penelitian quasi eksperimen. Populasi penelitian adalah seluruh siswa lelas X yang berjumlah 100 orang. Hasil uji homogenitas mendapatkan 2 kelas yang terpilih yaitu kelas X Mipa 1 dan X Mipa 2.dengan total sampel 67 orang. . Hasil belajar siswa pada penelitian ini dilihat dari selisih nilai pretest dan postest. Pada kelas yang menggunakan model pembelajaran PBL (X Mipa 1) nilai rata-rata peningkatan hasil belajar kognitif siswa sebesar 49,23. Sedangkan kelas yang menggunakan model pembelajaran TTW (X Mipa 2) , nilai rata-rata peningkatan hasil belajar kognitif siswa sebesar 56,33. Uji statistik dilakukan dengan menggunakan uji-t (α = 0,01) diperoleh t hitung = 3,53 > t tabel = 2,38. Hasil penelitian menunjukkan terdapat perbedaan hasil belajar yang signifikan antara kelas yang menggunakan model pembelajaran PBL dan kelas yang menggunakan model pembelajaran TTW. Kata Kunci : Model pembelajaran, Problem Based Learning, Think Talk Write, Hasil Belajar
[ANALYSIS OF Hg 2+ USING NANOPARTIKEL METAL (NPP) AS A COLORIMETRY INDICATOR WITH SPECTRUMFOTOMET... more [ANALYSIS OF Hg 2+ USING NANOPARTIKEL METAL (NPP) AS A COLORIMETRY INDICATOR WITH SPECTRUMFOTOMETRY METHOD]. Mercury (Hg) is heavy metal with high toxicity that often pollutes the aquatic environment. Concentration of Hg (II) ions is usually determined by using ICP-MS and AAS but because its price relatively expensive an alternative is needed to determine concentration of Hg. Therefore, the purpose of the study was to conduct synthesis of silver nanoparticles (NPP) by utilizing extract of Phyllanthus acidus ceremin fruit as a colorimetric indicator for alternative analysis concentration of Hg metal in digital image. Bio NPP used as a colorimetric indikator of Hg metal in this study was synthesized at optimum condition. The optimum condition of Bio NPP synthesis was obtained on the ratio of extract volume of P. acidus fruit and AgNO 3 1: 1 and the duration of exposure to sunlight for 1 hour.The formed Bio NPP knew to be selective against Hg (II) metal ions characterized by the change of Bio NPP color from brownish yellow to clear. In addition, the Bio NPP that has been synthesized in this study can be used as a colorimetric indicator of Hg metal analysis using spectrofotometer uv-vis with detection limit 7.56 ppb. Abstrak Merkuri (Hg) merupakan logam berat dengan toksisitas tinggi yang seringkali mencemari lingkungan perairan.Konsentrasi ion Hg(II) biasanya ditentukan dengan menggunakan alat ICP-MS dan AAS namun karena harganya yang relatif mahal maka diperlukan alternatif untuk menentukan konsentrasi Hg. Maka dari itu tujuan dari penelitian ini adalah untuk melakukan sintesis Bio nanopartikel perak (NPP) dengan memanfaatkan ekstrak buah Phyllanthus acidus ceremin sebagai indikator kolorimetri untuk alternatif analisis konsentrasi logam Hg secara citra digital. Bio NPP yang digunakan sebagai indikator kolorimetri logam Hg pada penelitian ini disintesis pada kondisi optimum.Kondisi optimum sintesis Bio NPP diperoleh pada perbandingan volume ekstrak buah Phyllanthus acidus ceremin dan AgNO 3 1 : 1 dan lama waktu penyinaran dengan cahaya matahari selama 1 jam. Bio NPP yang terbentuk diketahui selektif terhadap ion logam Hg(II) yang ditandai dengan berubahnya warna Bio NPP dari kuning kecoklatan menjadi bening. Selain itu Bio NPP yang telah disintesis pada penelitian ini dapat digunakan sebagai indikator kolorimetri analisis logam Hg meggunakan spektrofotometer UV-Vis dengan limit deteksi 7.56 ppb. Kata kunci : merkuri, buah ceremin, nanopartikel perak, indikator kolorimetri
[IMPLEMENTATION OF 2013 CURRICULUM FOR CHEMICAL TEACHERS IN SMA Negeri AT BENGKULU ] This researc... more [IMPLEMENTATION OF 2013 CURRICULUM FOR CHEMICAL TEACHERS IN SMA Negeri AT BENGKULU ] This research is a description research conducted from SMA Negeri 1 to SMA Negeri 10 Kota Bengkulu for chemistry teacher in 2016/2017 academic year. This study aims to describe the implementation of the 2013 curriculum for chemistry teachers in the SMA Negeri in Bengkulu City. The population of this research is all the chemistry teachers who teach in ten SMA Negeri in Bengkulu consisting of 42 teachers. Samples were taken by proportional random sampling technique as much as 20%, but the samples taken are teachers who have implemented the curriculum 2013. Obtained final sample of 26 teachers. In this study, a questionnaire was used to collect data, including indicators of the overall implementation of the curriculum, scattered on 53 points of statement, using Likert Scale with a score of 1 to 4. which was then processed using Statistical Product Service Solution(SPSS)16 program. The results showed that the implementation of the 2013 curriculum, the average percentage of teachers who have implemented is 66.67% with the category mostly implemented. Specifically that is, planning obtained at 65,385%, implementation obtained at 57,692%. and assessment of learning result obtained at 76,923% with category mostly executed.
[CONVERSION OF LIQUID WASTE OIL PALM OIL FACTORY BECOME BIOFUEL WITH MONi / HZ CATALYST] This stu... more [CONVERSION OF LIQUID WASTE OIL PALM OIL FACTORY BECOME BIOFUEL WITH MONi / HZ CATALYST] This study aims to produce biofuel from liquid waste oil PMKS with worditik cracking using catalystMoNi / HZ. This study involves the preparation of a catalyst performed by means of a separate impregnation, this impregnation lasting for 12 hours. The next stage of sample preparation includes heating, filtering, degumming, bleaching and ALB determination, followed by the production of methyl esters through esterification and transesterification processes. Then the obtained methyl ester was cracked using a catalyst for 2 hours at 380 °C and followed by distillation of the product for 2 hours at 380 °C, followed by distillation step at 380 °C to obtain methyl ester. The physical characteristics of biofuel resulting from the catalytic cracking reaction of the methyl ester using the MoNi / HZ catalyst of the PMKS wastewater include the acid number 1.92 mg KOH / g, density 0.803 g/cm 3 , kinematic viscosity 1,113 cSt, a pour poin of 0 o C and fog poin at 1,43 o C. Biofuel resulting from catalytic cracking using this MoNi / HZ catalyst of very high biofuel acid numbers can be used in areas that have a cold climate. the biofuel viscosity of the experimental results has not matched the viscosity of gasoline or kerosene, so it can not be used as fuel equivalent to gasoline and kerosene with the composition of 100% biofuel density from biofuel is still slightly above gasoline and kerosene Keyword : Biofuel, MoNi/HZ catalysts, PMKS liquid waste Abstrak Penelitian ini bertujuan untuk menghasilkan biofuel dari minyak limbah cair PMKS dengan perengkahan kataitik menggunakan katalis MoNi/HZ. Katalis yang digunakan disiapkan dengan cara mencampurkan zeolit alam (HZ) dengan .9 O melalui proses refluks pada suhu 90 o C selama 12 jam, disaring dan dikeringkan pada suhu 110 o C selama 3 jam dan selanjutnya diaktivasi dengan kalsinasi pada 500 o C menghasilkan katalis Ni-HZ. Proses impregnasi kedua , katalis Ni-HZ dicampurkan dengan (NH 4) 6 Mo 7 O 24 .4H 2 O , lalu direfluks pada suhu 90 o C selama 12 jam, disaring dan dikeringkan pada suhu 110 o C selama 3 jam dan selanjutnya diaktivasi dengan kalsinasi pada 500 o C menghasilkan katalis MoNi-HZ..Sampel limbah dipreparasi melalui tahapan pemanasan, penyaringan, degumming, bleaching dan penentuan ALB, dilanjutkan dengan pembuatan metil ester melalui proses esterifikasi dan transesterifikasi. Metil ester yang didapat direngkah menggunakan katalis MoNi-HZ selama 2 jam pada suhu 380 o C dan dilanjutkan dengan destilasi hasil selama 2 jam pada suhu 380 o C, untuk memperoleh metil ester. Karakteristik biofuel hasil perengkahan memiliki angka asam 1,92 mg KOH/g, densitas 0,803 g/cm 3 , viskositas kinematik 1,113 cSt, titik tuang 0 o C dan titik kabut 1,43 o C. Hasil penelitian menunjukkan bahwa karakteristik biofuel hasil dari perengkahan ini masih belum bisa digunakan secara langsung sebagai bahan bakar yang setara dengan bensin dan kerosin pada komposisi 100% biofuel. Kata Kunci : Biofuel, katalis MoNi/HZ, Metil Ester, limbah cair PMKS
[COMPARISON OF STUDENT LEARNING OUTCOMES BEETWEN INDEX CARD MATCH AND BAMBOO DANCING LEARNING MET... more [COMPARISON OF STUDENT LEARNING OUTCOMES BEETWEN INDEX CARD MATCH AND BAMBOO DANCING LEARNING METHOD] In the learning process teachers often use lecture methods so that students tend to only accept what is given by teachers and many students who feel chemistry lessons are difficult and confusing lessons. This results in low student learning outcomes. One effort that can be done by using the teacher method is varied, one of which is the method of Index Card Match and Bamboo Dancing. This research type is experiment. The population is all students in class X MIPA SMA Negeri 2 Kota Bengkulu as many as 216 students. The sample selection was done by homogeneity test with the result obtained by class X MIPA C (experimental class I) which applied Index Card Match method and X MIPA D (experiment II class) applying Bamboo Dancing method. Data analysis used is normality test, homogeneity test and t test. In this study the results of learning are seen the value of the difference between the average pretest and posttest, where obtained for class X MIPA C is 53.75 and class X MIPA D is 45.55. Then t test is obtained where t test t > t table (3,76 > 2,38), so it can be concluded that there is a significant difference between student learning result using Index Card Match method with Bamboo Dancing on chemical compound nomenclature material. Abstrak Dalam proses pembelajaran guru sering menggunakan metode ceramah sehingga siswa cenderung hanya menerima apa yang diberikan oleh guru dan banyak siswa yang merasa pelajaran kimia adalah pelajaran yang sulit dan membingungkan. Hal ini menyebabkan hasil belajar siswa rendah.Salah satu upaya yang dapat dilakukan guru yaitu dengan menggunakan metode yang bervariasi, salah satunya yaitu metode Index Card Match dan Bamboo Dancing. Jenis penelitian ini adalah eksperimen. Populasi adalah semua siswa di kelas X MIPA SMA Negeri 2 Kota Bengkulu sebanyak 216 siswa. Pemilihan sampel dilakukan dengan uji homogenitas dengan hasil didapatkan kelas X MIPA C (kelas eksperimen I) yang menerapkan metode Index Card Match dan X MIPA D (kelas eksperimen II) yang menerapkan metode Bamboo Dancing. Analisa data yang digunakan yaitu uji normalitas, uji homogenitas dan uji t. Pada penelitian ini hasil belajar yang dilihat yaitu nilai dari selisih rata-rata pretest dan posttest, dimana diperoleh untuk kelas X MIPA C yaitu 53.75 dan kelas X MIPA D yaitu 45.55. Kemudian dilakukan uji t dimana diperoleh t hitung > t tabel (3,76> 2,38), sehingga dapat disimpulkan bahwa terdapat perbedaan yang signifikan antara hasil belajar siswa yang menggunakan metode Index Card Match dengan Bamboo Dancing pada materi tata nama senyawa kimia.
[PHYTOCHEMICAL SCREENING AND ANTIOXIDANT ACTIVITY OF SOME FRACTIONS FROM BARK OF CASTOR (Ricinus ... more [PHYTOCHEMICAL SCREENING AND ANTIOXIDANT ACTIVITY OF SOME FRACTIONS FROM BARK OF CASTOR (Ricinus communis L.)]. The Phytochemical screening was conducted to determine secondary metabolites found in the bark of castor (Ricinus communis L.).The test results of phytochemical screening that has been done presence of phenolic, flavonoids, alkaloids, saponins, and terpenoids. Extraction is done by maceration using ethanol 96%. Tests performed on the fraction of the antioxidant activity of ethanol, ethyl acetate, n-hexane, and ascorbic acid as compared to using DPPH. The results of measuring the antioxidant activity using Uv-Vis Spectrophotometer IC 50 values obtained succession namely fraction of ethanol, ethyl acetate, n-hexane, and ascorbic acid, 33,38, 24,38, 289, 05 and 12, 48 ppm. Fraction of ethanol and ethyl acetate has a very strong antioxidant activity due IC 50 <50 ppm while the n-hexane fraction very weak antioxidant activity. Phenolic and flavonoids the bark of castor that can be potentially as antioxidants
[RELATIONS OF STUDENTS PERCEPTION AND VARIATION TEACHING STYLE WITH CHEMISTRY LEARNING OUTCOMES A... more [RELATIONS OF STUDENTS PERCEPTION AND VARIATION TEACHING STYLE WITH CHEMISTRY LEARNING OUTCOMES AT CLASS X MIPA IN SMA NEGERI KOTA BENGKULU IN 2016/2017 ACADEMICS YEAR ] In teaching and learning activities at school, often faced with the problem of low student learning outcomes. Student learning outcomes is one indicator to measure success in the implementation of learning process. Student learning outcomes are influenced by several factors, both external and internal factors. One of the internal factors that can affect student learning outcomes is perception. The object of perception here is the variation of the teacher's teaching style. The purpose of this study is to obtain data about students' perceptions about the variation of teaching style of chemistry teacher and student chemistry learning outcomes in SMA Negeri Kota Bengkulu academic year 2016/2017. Polpulation in this research is all students of class X of MIPA in State Senior High School of Bengkulu which amounted to 1620 students. The technique of determining the sample that will be used by the researcher is Proportional Random Sampling technique and the sample is 324 students. Data analysis used in this research is descriptive analysis, normality test, linearity, correlation and hypothesis test. Based on the analysis, the correlation coefficient value is 0.232 > 0.11 (r count t > r table), and t count > t table (4,312 > 1,967), indicating that there is a significant positive correlation between students' perception about teacher teaching style variation and student's chemistry learning result. Abstrak Pada kegiatan belajar mengajar disekolah, sering kali dihadapkan pada masalah rendahnya hasil belajar siswa. Hasil belajar siswa merupakan salah satu indikator untuk mengukur keberhasilan dalam pelaksanaan proses pembelajaran. Hasil belajar siswa dipengaruhi oleh beberapa faktor, baik faktor ekternal maupun faktor internal. Salah satu faktor internal yang dapat mempengaruhi hasil belajar siswa adalah persepsi. Yang menjadi objek dari persepsi disini adalah variasi gaya mengajar guru. Tujuan penelitian ini adalah untuk memperoleh data mengenai persepsi siswa tentang variasi gaya mengajar guru kimia dan data hasil belajar kimia siswa di SMA Negeri Kota Bengkulu tahun ajaran 2016/2017. Polpulasi dalam penelitian ini adalah seluruh siswa kelas X MIPA di SMA Negeri Kota Bengkulu yang berjumlah 1620 siswa. Teknik penentuan sampel yang akan digunakan peneliti yaitu teknik Proportional Random Sampling dan didapatkan sampel sebanyak 324 siswa. Analisis data yang digunakan pada penelitian ini adalah analisa deskriptif, uji normalitas, linieritas, korelasi dan uji hipotesis. Berdasarkan analisis diperoleh nilai koefisien korelasi 0,232>0,11 (r hitung > r tabel), dan nilai t hitung > t tabel (4,312>1,967), yang menunjukkan bahwa ada hubungan positif yang signifikan antara persepsi siswa tentang variasi gaya mengajar guru dengan hasil belajar kimia siswa.
Antioxidant agents play an important role in inhibiting free radical molecules activity thus prev... more Antioxidant agents play an important role in inhibiting free radical molecules activity thus preventing the cancer disease. This current study aimed to evaluate antioxidant and cytotoxicityproperties of ethyl acetate fractions of Pandanustectorius fruit extract on HeLa cell lines. The radical scavenging activity was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The cytotoxicity was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against human HeLa cell lines. The result showed that all ethyl acetate fractions of P. tectoriusfruit had high antioxidant property. All of seven fractions of the ethyl acetate extract were observed based on the IC 50 value and had high DPPH free radical scavenging activity with the IC 50 value range from 0.3 to 2.4 mg/ml compare to positive control,quercetin(IC 50 = 0.2 mg/ml). Based on the DPPH free radical scavenging activity (antioxidant property), three of seven fractions were chosen for the MTT assay to analyze their cytotoxic activity as anticancer potential agent against HeLa cell lines.From MTT result, one of tree fractions were showed cytotoxicity activity against HeLa cell lines with the IC 50 value is 12 µg/ml (less than 30 µg/ml), while anothertwo fractions was found not cytotoxic against HeLa cell lines.It is clearly indicated that P. tectoriusfruit has a very good potential as antioxidant and anticancer agent.
[RELATIONSHIP BETWEEN LABORATORY FACILITIES AND STUDENT PROCESS SKILLS AT CLASS XI MIPA 5 IN SMA ... more [RELATIONSHIP BETWEEN LABORATORY FACILITIES AND STUDENT PROCESS SKILLS AT CLASS XI MIPA 5 IN SMA NEGERI 3 KOTA BENGKULU] The purpose of this study was to determine the relationship of laboratory facilities to students' science process skills in the laboratory. This research is a correlational research. The population in this study is all students of class XI MIPA 5 academic year 2016/2017 in SMA Negeri 3 Kota Bengkulu. This research uses total sampling technique so that the entire population is used as research sample. The independent variable (x) in this research is chemical laboratory equipment and dependent variable (y) is the science process skill of students in laboratory of SMA Negeri 3 Kota Bengkulu.. Data collection in this research using questionnaire instrument with 30 items and observation sheet with 15 items. Technique of data analysis using expert validity test, questionnaire analysis, observation analysis of science process skill, normality test, linearity test, correlation analysis and hypothesis test. Data analysis using the help of SPSS 16 program. The results of data processing correlation coefficient (r) obtained that is equal to 0.387 at 5% significance level.. The result of hypothesis test shows that Ha is accepted which means there is a significant correlation between laboratory facilities and science process skill of students in laboratory on chemistry learning of students of class XI MIPA 5 SMA Negeri 3 Kota Bengkulu academic year 2016/2017 Abstrak Tujuan penelitian ini adalah untuk mengetahui hubungan sarana laboratorium terhadap keterampilan proses sains siswa di laboratorium. Penelitian ini merupakan penelitian korelasional. Populasi pada penelitian ini adalah seluruh siswa-siswi kelas XI MIPA 5 tahun ajaran 2016/2017 di SMA Negeri 3 Kota Bengkulu. Penelitian ini menggunakan teknik total sampling sehingga seluruh populasi digunakan sebagai sampel penelitian. Variabel bebas (x) pada penelitian ini adalah sarana laboratorium kimia dan variabel terikat (y) adalah keterampilan proses sains siswa di laboratorium SMA Negeri 3 Kota Bengkulu.Teknik pengumpulan data pada penelitian ini menggunakan instrument angket dengan 30 butir pertanyaan dan lembar observasi dengan 15 butir pertanyaan.. Teknik analisis datanya menggunakan uji validitas ahli, analisis angket, analisis observasi keterampilan proses sains, uji normalitas, uji linearitas, analisis korelasi dan uji hipotesis. Analisis data menggunakan bantuan program SPSS 16. Hasil dari pengolahan data koefisien korelasi (r) yang diperoleh yaitu sebesar 0,387 pada taraf signifikansi 5%.. Hasil uji hipotesis yang diperoleh menunjukkan bahwa H a diterima yang artinya terdapat hubungan yang signifikan antara sarana laboratorium dan keterampilan proses sains siswa di Laboratorium pada pembelajaran kimia siswa-siswi kelas XI MIPA 5 SMA Negeri 3 Kota Bengkulu tahun ajaran 2016/2017 .
[ANALYSIS OF SILICA ADSORPTION CAPACITY FROM THE SAND OF PANTAI PANJANG BENGKULU AGAINST RHODAMIN... more [ANALYSIS OF SILICA ADSORPTION CAPACITY FROM THE SAND OF PANTAI PANJANG BENGKULU AGAINST RHODAMINE B DYES ] This research was aimed to study the adsorption capacity of synthetic silica on Rhodamine B dyes. Synthetic silica was obtained from the sand of Pantai Panjang Bengkulu by alkali fusion method using KOH at 360 °C for 4 hours in furnace to obtain potassium silicate crystals (K 2 SiO 3). The crystals were then added 500 mL aqua DM, stirred and sterilized for 24 hours folloed by filtered. The filtrate was dropped with 10 M HCl solution until the pH of filtrate solution reached at 1 to 2 and formed a silent white gel for 24 hours. Moreover, the gel was filtered with filter paper and washed with aqua DM until pH is neutral and free from KCl, and dried in an oven at 60 °C for 18 hours. The obtained silica powder is then smoothed with mortar and weighed. The adsorbent of Rhodamine B dyes using the synthetic silica powder was performed on pH variation at 2, 3, 4, 5, 6, and 7 , and variation of contact time at 10, 20, 30, 40, 50, and 60 min. The results showed that the optimum condition of adsorption of Rhodamine B by silica from Pantai Panjang sand occured at optimum pH 2 and optimum contact time 20 minutes; with adsorption capacity of 4.95 mg / g and 4.79 mg/g; and with adsorption efficiency of 99.00% and 95.89%. Abstrak Penelitiaan ini bertujuan untuk mempelajari kapasitas adsorpsi silika pada Rhodamin B. Sintesis silika diperoleh dari pasir Pantai Panjang Bengkulu dengan metode alkali fusion menggunakan KOH dalam furnace bersuhu 360°C selama 4 jam, untuk memperoleh kristal kalium silikat (K 2 SiO 3).. Kristal kemudian ditambahkan aquademin sebanyak 500 ml , diaduk, dan didiamkan selama 24 jam, disaring dan filtrat ditetesi dengan larutan HCl 10 M hingga pH filtrate mencapai pH 1 hingga 2 dan terbentuk gel putih yang didiamkan selama 24 jam, selanjutnya gel disaring dengan kertas saring dan dicuci dengan aquademin hingga pH netral dan bebas dari KCl, dikeringkan dalam oven pada suhu 60 °C selama 18 jam. Serbuk silika yang diperoleh selanjutnya dihaluskan dengan mortar dan ditimbang. Adsorpsi Rhodamin B menggunakan silika hasil sintesis dilakukan pada variasi pH 2, 3, 4, 5, 6, dan 7 dengan variasi waktu kontak 10, 20, 30, 40, 50, dan 60 menit. Hasil penelitian menunjukkan bahwa kondisi optimum adsorpsi Rhodamin B oleh silika dari pasir Pantai Panjang dengan pH optimum terjadi pada pH 2 dan waktu kontak optimum 20 menit; dengan kapasitas adsorpsi sebesar 4,95 mg/g dan 4,79 mg/g; dan dengan efisiensi adsorpsi sebesar 99,00 % dan 95,89 %.
[COMPARISON OF STUDENTS LEARNING RESULT USING MEDIA Daily Chem Quiz AND GAMES Ranking One Chemist... more [COMPARISON OF STUDENTS LEARNING RESULT USING MEDIA Daily Chem Quiz AND GAMES Ranking One Chemistry Quiz] The aim of this research is to know the difference of students' chemistry learning result using Daily Chem Quiz (DC Quiz) and Ranking One Chemistry Quiz (ROC Quiz) media at class X MIPA in SMA Negeri 1 Bengkulu Tengah 2016 / 2017 academic year. This research is quasi research experiment. The independent variables are DC Quiz and ROC Quiz media, the dependent variable is the students' learning result and the control variable is the Think-Pair-Share (TPS) cooperative learning methods. The population is all students of class X MIPA at 2016/2017 academic year consisting of 4 classes, and to determine the sample is done by homogeneity test then taken by simple random sampling. The selected sample is the class X MIPA 3 as experiment class I using DC Quiz and class X MIPA 1 as experimental class II using RC Quiz. Data analysis used were mean score, normality test, homogeneity test, and t test. Based on posttest value of both class, it is known that the average value of posttest at experiment class I is 78.79 and at experiment class II is 84,77. The result of data analysis shows that the data is normally distributed and has homogeneous variance and obtained t count> t tabel (2,47> 2,39). The results of this study indicate that H 0 rejected and H a accepted in other words there is a significant difference between student learning outcomes using DC Quiz media and RC Quiz media. Abstrak Penelitian ini bertujuan untuk mengetahui perbedaan hasil belajar kimia siswa menggunakan media Daily Chem Quiz (DC Quiz) dan Ranking One Chemistry Quiz, (ROC Quiz) pada kelas X MIPA di SMA Negeri 1 Bengkulu Tengah Tahun ajaran 2016/2017.Penelitian ini merupakan penelitian kuasi eksperimen. Variabel bebas pada penelitian ini adalah media DC Quiz dan media ROC Quiz, variabel terikat adalah hasil belajar kimia siswa dan variable kontrol yaitu pembelajaran kooperatif tipe Think-Pair-Share (TPS). Populasi dalam penelitian ini yaitu siswa kelas X MIPA tahun pelajaran 2016/2017 yang terdiri dari 4 kelas, dan untuk menentukan sampel dilakukan uji homogenitas yang kemudian diambil secara simple random sampling. Sampel yang terpilih yaitu siswa kelas X MIPA 3 sebagai kelas eksperimen I menggunakan media DCQ dan X MIPA 1 sebagai kelas eksperimen II menggunakan media RCQ. Analisa data yang digunakan adalah nilai rata-rata, uji normalitas, uji homogenitas, dan uji t. Berdasarkan nilai posttest kedua kelas eksperimen, diketahui nilai rata-rata posttest kelas eksperimen I adalah 78,79 sedangkan untuk kelas eksperimen II adalah 84,77. Hasil analisis data menunjukkan bahwa data berdistribusi normal dan memiliki varians yang homogen serta diperoleh t hitung > t tabel (2,47 > 2,39). Hasil penelitian ini menunjukkan bahwa H 0 ditolak dan H a diterima dengan kata lain terdapat perbedaan yang signifikan antara hasil belajar siswa yang menggunakan media DCQ dan RCQ..
[DETERMINATION OF ETHYL ACETATE FRACTION FROM Peronema canescens LEAF EXTRACT AGAINST Plasmodium ... more [DETERMINATION OF ETHYL ACETATE FRACTION FROM Peronema canescens LEAF EXTRACT AGAINST Plasmodium berghei INFECTED Mus musculus] This study was conducted to identify secondary metabolite compounds contained in ethanol extract and ethyl acetate fraction from Peronema canescens leaf (sungkai) and to measure the effect of ethyl acetate fraction on anti plasmodium activity on Mus musculus infected by Plasmodium berghei. The ethyl acetate extract was obtained by maceration of leaves with 96% ethanol solution in3 days followed by fractionation by ethyl acetate for further test. 25 of male white M. musculus with the weight 20-40 g and 6-8 weeks old , divided into 5 groups with 5 head / group. Groups 3, 4 and 5 are treated and groups 1 and 2 are controls. The negative control will be given food and drink only, and for positive control group will be given chloroquine with dose 0,028, 0,056, and 0,084 g / KgBW. Development of levels of parasitemia were calculated by by observing a thin blood smear with giemsa staining under a microscope , observed until the parasitemia in the blood had reached 20-30% to be given a 3-day follow-up treatment, and then for the next 7 days after it was given treatment.. Anti-plasmodium activity test is determined by the number of parasitemia, percent growth and resistance of parasitemia in the blood. Data were analyzed by using one way anova method (α = 0,05 and 0,01). The results showed that the secondary metabolite compounds found in the ethyl acetate fraction of P.canescens leaf, namely alkaloids, flavonoids, tannins and phenolics and at a dose of 0.056 g / KgBW ethyl acetate fraction can inhibit the growth of parasitemia in the blood of M. musculus by 50 , 89% , with greater percentage of parasitemic inhibition compared with positive and negative control group. Abstrak Penelitian ini dilakukan untuk mengidentifikasi senyawa metabolit sekunder yang terdapat dalam ekstrak etanol dan fraksi etil asetat dari daun Peronema canescens (sungkai) serta untuk mengukur pengaruh pemberian fraksi etil asetat terhadap aktivitas anti plasmodium pada Mus musculus (mencit) jantan yang terinfeksi Plasmodium berghei. Ekstrak diperoleh dari hasil maserasi daun P.canescens dengan etanol 96% selama 3 hari, dilanjutkan dengan fraksinasi dengan etil asetat daun P.canescens Sebanyak 25 ekor M. Musculus putih jantan dengan berat badan 20-40 g dan berumur 6-8 minggu , dibagi menjadi 5 kelompok masing masing 5 ekor/ kelompok. Kelompok 3, 4 dan 5 merupakan kelompok perlakuan dan kelompok 1 dan 2 merupakan kelompok kontrol. Untuk kelompok perlakuan kontrol negatif hanya akan diberikan pakan dan minum saja , untuk kelompok kontrol positif akan diberikan klorokuin dengan dosis 0,028, 0,056 dan 0,084 g/KgBB. Tingkat perkembangan parasitemia dihitung dari pengamatan apusan darah M.musculus dengan pewarnaan giemsa dibawah mikroskop. Bila parasitemia dalam darah telah mencapai 20-30% , diberikan perlakuan lanjut selama 3 hari, dan kemudian dihitung untuk 7 hari berikutnya. Uji aktifitas anti plasmodium ditentukan oleh jumlah parasitemia, persen pertumbuhan dan hambatan parasitemia dalam darah. Data dianalisis dengan menggunakan metode one way anova (α=0,05 dan 0,01). Hasil penelitian menunjukkan bahwa senyawa metabolit sekunder yang terdapat pada fraksi etil asetat daun P.canescens yaitu alkaloid, flavonoid, tanin dan fenolik serta pada dosis 0,056 g/KgBB fraksi etil asetat P. canescens dapat menghambat pertumbuhan parasitemia sebesar 50,89%., dimana lebih besar persentase penghambatannya dibandingkan terhadap kelompok kontrol positif dan negatif.
[COMPARISON STUDY OF COOPERATIVE LEARNING USING CHEMICAL DOMINO CARD AND FLASH CARD MEDIA] This s... more [COMPARISON STUDY OF COOPERATIVE LEARNING USING CHEMICAL DOMINO CARD AND FLASH CARD MEDIA] This study aims to measure differences in the results of chemistry learning between experimental class 1 classes that apply Chemical Domino Card learning media with experimental class 2 that apply Flash Card media at nomenclature of chemical compounds topics in class X IPA SMA Negeri 2 Kota Bengkulu at 2016 / 2017 academic year. Use of these two learning media is considered from the practicality, advantages, and effectivenes The type of research is a quasi experimental research with the population of all students of class X MIPA in SMA Negeri 2 Kota Bengkulu at 2016/2017 academic year , which a sample class is X MIPA E and X MIPA F. Implementation of research conducted by using two experimental class, X MIPA E which uses Chemical Domino Card media and class X MIPA F using Flash Card media. Data analysis used are mean value, homogeneity test, normality test and t test. The average value of posttest experimental class I for first and second meeting is 77,5 and 79,72, while for experiment class II is 86,94 and 88,61. Then t test is done by using difference of pretest and posttest value of student, which is obtained that both at first meeting and second t count> t table that is 2,44> 2,38081 (first meeting) and 2,81> 2,38081 (second meeting). The results of this study indicate that there is a significant difference of student learning outcomes using Chemical Domino Card and Flash Card media on the nomenclature of chemical compounds. Abstrak Penelitian ini bertujuan untuk mengukur perbedaan hasil belajar kimia antara kelas kelas eksperimen 1 yang menerapkan media pembelajaran Chemical Domino Card dengan kelas eksperimen 2 yang menerapkan media pembelajaran Flash Card pada materi materi tata nama senyawa kimia di kelas X IPA di SMA Negeri 2 Kota Bengkulu tahun ajaran 2016/2017.Penggunaan kedua media pembelajaran ini dipertimbangkan dari kepraktisan, kelebihan, dan efektif untuk dilakukan. Jenis penelitian yang digunakan adalah penelitian kuasi eksperimen dengan populasi seluruh siswa kelas X MIPA di SMA N 2 Kota Bengkulu tahun ajaran 2016/2017 dan sampel penelitian adalah kelas X MIPA E dan kelas X MIPA F. Pelaksanaan penelitian dilakukan menggunakan dua kelas eksperimen, yaitu kelas X MIPA E menggunakan media Chemical Domino Card dan kelas X MIPA F menggunakan media Flash Card. Analisa data yang digunakan adalah nilai rata-rata, uji homogenitas, uji normalitas dan uji t. Nilai rata-rata postest kelas eksperimen I untuk pertemuan pertama dan kedua adalah 77,5 dan 79,72, sedangkan untuk kelas eksperimen II adalah 86,94 dan 88,61. Kemudian dilakukan uji t dengan menggunakan selisih nilai pretest dan postest siswa, yang mana diperoleh bahwa baik pada pertemuan pertama dan kedua t hitung >t tabel yaitu adalah 2,44>2,38081 (pertemuan pertama) dan 2,81>2,38081 (pertemuan kedua). Hasil penelitian ini menunjukkan bahwa terdapat perbedaan yang signifikan dari hasil belajar siswa yang menggunakan media Chemical Domino Card dan Flash Card pada materi tata nama senyawa kimia.
[ANTIOXIDANT ACTIVITY OF SECONDARY METABOLITE FROM ENDOFIT BACTERIA OF Moringa oleifera L (KELOR)... more [ANTIOXIDANT ACTIVITY OF SECONDARY METABOLITE FROM ENDOFIT BACTERIA OF Moringa oleifera L (KELOR) ROOTS] The purpose of this research was aims to isolate and measure the ability of antioxidant activity from secondary metabolites produced by endophytic bacteria that grow in the live tissue root of Moringa oleifera L. (kelor). Endophytic bacteria were purified and cultured using a solid Murashige-skoog (MS) medium for 3 days at room temperature. Secondary metabolites were obtained by centrifugation process at a rate of 3000 rpm for 20 minutes. The bacterial fermentation process using Nutrient Broth (NB) medium for 72 hours with a shaker speed at 170 rpm. The suspension supernatant was extracted with a maceration method using 86% ethyl acetate, followed by vacuum rotary evaporator concentration at 40 ° C. The extract antioxidant activity test was performed using the DPPH (1,1-diphenyl-2-picrylhydrazyl) method using a UV-Vis spectrophotometer at 517 nm wavelength and ascorbic acid as standard. The result of DPPH test showed that the antioxidant activity of ethyl acetate extract of endophytic bacterial from root of M. oleifera L root has IC 50 value at 315, 396 ppm. Based on these results, it can be concluded that the secondary metabolite extract of endophytic bacterial from M. oleifera L root classified as weak antioxidant (IC50> 250 ppm). Abstrak Penelitian ini bertujuan untuk mengisolasi dan mengukur kemampuan aktivitas anti oksidan dari metabolit sekunder yang dihasilkan oleh bakteri endofit yang tumbuh di dalam jaringan hidup a kar Moringa oleifera L.(kelor). Bakteri endofit dimurnikan dan dibiakkan menggunakan medium padat Murashige-skoog (MS) selama 3 hari pada suhu ruang. Metabolit sekunder didapatkan melalui proses sentrifugasi dengan kecepatan 3000 rpm selama 20 menit.dari suspensi hasil proses fermentasi bakteri menggunakan medium Nutrient Broth (NB) selama 72 jam dengan kecepatan shaker 170 rpm. Supernatan yang didapatkan selanjutnya diekstraksi dengan metode maserasi menggunakan etil asetat 86 %, , dilanjutkan pemekatan dengan vacuum rotary evaporator pada suhu 40 o C. Uji aktivitas antioksidan ekstrak dilakukan dengan menggunakan metode DPPH (1,1-difenil-2-pikrilhidrazil) menggunakan spektrofotometer UV-Vis pada panjang gelombang 517 nm dan asam askorbat sebagai standar. Hasil u j i D P P H menunjukkan bahwa aktivitas antioksidan ekstrak etil asetat bakteri endofit akar M. oleifera L memiliki nilai IC50 sebesar 315, 396 ppm. Ber dasarkan has il t er sebut , dapat dis i mpu lkan ba hwa ekst r ak met abo lit sekunder bakt er i endo fit akar M. oleifera L t er go lo ng a nt io ksida n le ma h (I C 50 > 250 ppm). Kata kunci : Antioksidan, bakteri endofit, Moringa oleifera L. Kelor.
The problem of environmental polution caused by waste of batik industry lately is increasing, so ... more The problem of environmental polution caused by waste of batik industry lately is increasing, so it needed a method to overcome that problem. The aim of this study was to determine the ability of activated charcoal from coconut fiber palm in adsorbing Reactive Red-120 and Direct Green-26 dyes in waste of batik along with determining the parameters of isotherms adsorption using UV-Vis Spectrophotometer analysis method. Variations of pH, contact time, adsorbent weight and temperature were carried out as variable to obtain optimum conditions of the adsorption process. The optimum of conditions for Reactive Red-120 occured at pH 3 and a contact time of 30 minutes, while Direct Green-26 occurred at pH 4 and a contact time of 40 minutes, with each adsorbent weight 150 mg and the temperature 30°C. Adsorption isotherms determined by Freundlich and Langmuir models with maximum adsorption capacity (Qmax) were obtained for the Reactive Red-120 was 400 mg/g, while Direct Green-26 is 169 mg/g.
The purpose of this research is to know the difference of students' chemistry learning result bet... more The purpose of this research is to know the difference of students' chemistry learning result between experiment 1 class which applied learning cycle model (5E) with experiment 2 class that apply two stay two stray learning model on acid acid base material in class XI IPA in SMA Plus Negeri 7 Bengkulu City. Research conducted is a research with the type of quasi experiment. Chemical learning result data obtained from pretest value and posttest value where the average value of improvement of cognitive learning result for experiment class 1 is 47,78. And the average value of cognitive learning improvement for experiment class 2 is 54.875. With testing the hypothesis using t test with significant level (α = 0,01), then got value for titung equal to 2,60 and for ttable got value equal to 2,380. The results showed that there were significant differences in learning outcomes between classes that applied learning cycle model (5E) with classes that applied the two stay two stray learning model.
This study aims to determine the antioxidant activity of jarak kepyar’s leaf extracts (Ricinus c... more This study aims to determine the antioxidant activity of jarak kepyar’s leaf extracts (Ricinus communis L.) and to determine of the fraction the growth of Erwinia carotovora. Jarak kepyar’s leaf extracted by maceration method using ethanol and fractionated using n-hexane and ethyl acetate. Antioxidant test using DPPH (1,1-diphenyl-2-picrylhydrazyl) with various concentrations of 125 ppm, 100 ppm, 75 ppm, 50 ppm, 25 ppm, 15 ppm and 5 ppm. Antibacterial test conducted on the active fractions as antioxidants using paper disc method and variations in the concentration of 1000 ppm, 500 ppm, 250 ppm, 125 ppm, 62.5 ppm. Phytochemical test results jarak kepyar’s leaf contain secondary metabolites are alkaloids, flavonoids, phenols and terpenoids. The test results demonstrate the antioxidant activity of ethyl acetate fraction is very strong as an antioxidant with IC50 values of 5.4 ppm and a strong ethanol fraction categorized as antioxidants IC50 of 99.8 ppm. Antibacterial test results showed inhibition of the leaf fraction of jarak kepyar’s (Ricinus communis L.) against Erwinia carotovora categorized weak growth in ethanol fractions with inhibition zone diameter of 4 mm and being in ethyl acetate fraction with a diameter of 5 mm.
The average students' chemical learning outcomes are still low, the low learning outcome is influ... more The average students' chemical learning outcomes are still low, the low learning outcome is influenced by several factors, including students still consider that chemistry as one of the scary, difficult to understand and less interesting lessons. Therefore, the research wants to vary the learning process in the classroom by applying the learning model of Discovery Learning with Group Investigation model. This research was aimed to find out the students’ achievement differences of chemical subject by using Discovery learning and Group Investigation model. The research is quasi experimental research. The population of this research were class X MIPA in SMAN 9 Bengkulu City, and the sample were X MIPA 2 and MIPA 3. This research using two experimental classes, that is class X MIPA 2 applying Group Investigation model and X MIPA 3 applying Discovery Learning model. Analysis of the data used is mean values, normality test, homogeneity test, and t-test. Post-test mean values for first experiment class is 78,12, but for second experiment class is 81,3. To determine whether the differences of student’s learning outcomes between both of experiment classes or not, we use t-test by using the differences between student’s pretest and posttest values, tcount > ttable (2,17 > 1,67). The result of this research showed that Ha accepted, in other words is a significant differences in learning outcomes of student’s applying Discovery Learning and Group Investigation model.
[ANTIXOXIDANT AND ANTIBACTERIA ACTIVITIES OF Strobilanthes crispus Bl (Keji Beling) EXTRACT AGAIN... more [ANTIXOXIDANT AND ANTIBACTERIA ACTIVITIES OF Strobilanthes crispus Bl (Keji Beling) EXTRACT AGAINST Stapylococcus Aureus AND Escherichia coli] Strobilanthes crispus Bl (Keji Beling) is one of herbs that has been used for the treatment of several types of diseases such as kidney stones, gall stones, diabetes, cholesterol, tumors and others. The purpose of this study was to determine the value of antioxidant activity (IC 50) and antibacterial activity of ethanol extract of leaf vermicelli against Staphylococcus aureus and Escherichia coli bacteria. Antioxidant test was performed using DPPH method and vitamin C was used as standard. While the antibacterial activity test done by paper disc method. Amphicillin is used as a positive control and aquades as a negative control. Ethanol extract of leaf vermicelli able to counteract free radical of DPPH with IC 50 value that is: 102.85 ppm and IC 50 value from vitamin C as comparative solution equal to 19.268 ppm. The results of antibacterial inhibition test of ethanol extract of vile leaf on S. aureus bacteria with extract concentration of 20% (0 mm), 40% (2.5 mm), 60% (3.25 mm), and 80% (4.75) were included Weak and 100% (5.75 mm) including Medium, and E.coli antibacterial inhibition in the extract contacts of 20% (0 mm), 40% (2 mm), 60% (2.25 mm), 80% (4.25 mm) were weak, and 100% (5.25 mm) including moderate. So it is known that the extract of ethanol leaves vile at 100% concentration can inhibit the growth of S. aureus bacteria and E. coli bacteria characterized by the formation of the largest clear zone diameter at the concentration. But the strength of its bacteria is still not effective to inhibit the growth of both test bacteria. Abstrak Strobilanthes crispus Bl (Keji Beling) merupakan salah satu tanaman herbal yang telah digunakan untuk pengobatan beberapa jenis penyakit antara lain batu ginjal, batu empedu, diabetes, kolesterol, tumor dan lain-lain. Tujuan dari penelitian ini adalah untuk menentukan nilai aktivitas antioksidan(IC 50) dan aktivitas antibakteri dari ekstrak etanol daun Strobilanthes crispus Bl terhadap bakteri Staphylococcus aureus dan Escherichia coli. Uji antioksidan dilakukan menggunakan metoda DPPH dengan vitamin C sebagai standar, dan uji aktivitas antibakteri dilakukan dengan metoda kertas cakram menggunakan Amphisilin sebagai kontrol positif dan aquades sebagai kontrol negatif. Ekstrak etanol daun S. crispus Bl mampu menangkal radikal bebas DPPH dengan nilai IC 50 yaitu: 102.85 ppm dan nilai IC 50 dari vitamin C sebagai larutan pembanding sebesar 19.268 ppm. Hasil uji daya hambat antibakteri ekstrak etanol daun S.crispus Bl pada bakteri S. aureus dengan konsentrasi ekstrak 20% (0 mm)
[COMPARISON FROM LEARNING OUTCOMES OF PROBLEM BASED LEARNING MODELS AND THINK TALK WRITE MODELS ]... more [COMPARISON FROM LEARNING OUTCOMES OF PROBLEM BASED LEARNING MODELS AND THINK TALK WRITE MODELS ] Each learning model has advantages and disadvantages in every process.This research intent to know the difference student studying result on chemical learning among brazes that utilize learning model Problem Based Learning (PBL) with class that utilize learning model Think is Write's Talc (TTW) on jurisdictional material – chemical base law at class X SMA Negeri 10 Kota Bengkulu's. This research constitute quasi's experiment. Students learned result on observational it is seen from pretest's point and posttest difference. On class that utilize Problem Based Learning (PBL) model , increasing average value from student kognitiv as big as 49,23. Meanwhile class that utilize Think is Write's Talc (TTW) model , increasing average value learned student kognitiv as big as 56,33. Hypothese was tested by use of t test (α = 0,01) to result at t test = 3,53 < t table = 2,38. Research result to point out that are distinctive result that significan among between class that utilize Problem Based Learning (PBL) model and class that utilize Think is Write's Talk (TTW) model. Abstrak Penelitian ini bertujuan untuk mengetahui perbedaan hasil belajar siswa pada pembelajaran kimia antara kelas yang menggunakan model pembelajaran Problem Based Learning (PBL) dengan kelas yang menggunakan model pembelajaran Think Talk Write (TTW) pada materi hukum – hukum dasar kimia di kelas X SMA Negeri 10 Kota Bengkulu Tahuyn ajaran 2016/2017. Penelitian ini merupakan penelitian quasi eksperimen. Populasi penelitian adalah seluruh siswa lelas X yang berjumlah 100 orang. Hasil uji homogenitas mendapatkan 2 kelas yang terpilih yaitu kelas X Mipa 1 dan X Mipa 2.dengan total sampel 67 orang. . Hasil belajar siswa pada penelitian ini dilihat dari selisih nilai pretest dan postest. Pada kelas yang menggunakan model pembelajaran PBL (X Mipa 1) nilai rata-rata peningkatan hasil belajar kognitif siswa sebesar 49,23. Sedangkan kelas yang menggunakan model pembelajaran TTW (X Mipa 2) , nilai rata-rata peningkatan hasil belajar kognitif siswa sebesar 56,33. Uji statistik dilakukan dengan menggunakan uji-t (α = 0,01) diperoleh t hitung = 3,53 > t tabel = 2,38. Hasil penelitian menunjukkan terdapat perbedaan hasil belajar yang signifikan antara kelas yang menggunakan model pembelajaran PBL dan kelas yang menggunakan model pembelajaran TTW. Kata Kunci : Model pembelajaran, Problem Based Learning, Think Talk Write, Hasil Belajar
[ANALYSIS OF Hg 2+ USING NANOPARTIKEL METAL (NPP) AS A COLORIMETRY INDICATOR WITH SPECTRUMFOTOMET... more [ANALYSIS OF Hg 2+ USING NANOPARTIKEL METAL (NPP) AS A COLORIMETRY INDICATOR WITH SPECTRUMFOTOMETRY METHOD]. Mercury (Hg) is heavy metal with high toxicity that often pollutes the aquatic environment. Concentration of Hg (II) ions is usually determined by using ICP-MS and AAS but because its price relatively expensive an alternative is needed to determine concentration of Hg. Therefore, the purpose of the study was to conduct synthesis of silver nanoparticles (NPP) by utilizing extract of Phyllanthus acidus ceremin fruit as a colorimetric indicator for alternative analysis concentration of Hg metal in digital image. Bio NPP used as a colorimetric indikator of Hg metal in this study was synthesized at optimum condition. The optimum condition of Bio NPP synthesis was obtained on the ratio of extract volume of P. acidus fruit and AgNO 3 1: 1 and the duration of exposure to sunlight for 1 hour.The formed Bio NPP knew to be selective against Hg (II) metal ions characterized by the change of Bio NPP color from brownish yellow to clear. In addition, the Bio NPP that has been synthesized in this study can be used as a colorimetric indicator of Hg metal analysis using spectrofotometer uv-vis with detection limit 7.56 ppb. Abstrak Merkuri (Hg) merupakan logam berat dengan toksisitas tinggi yang seringkali mencemari lingkungan perairan.Konsentrasi ion Hg(II) biasanya ditentukan dengan menggunakan alat ICP-MS dan AAS namun karena harganya yang relatif mahal maka diperlukan alternatif untuk menentukan konsentrasi Hg. Maka dari itu tujuan dari penelitian ini adalah untuk melakukan sintesis Bio nanopartikel perak (NPP) dengan memanfaatkan ekstrak buah Phyllanthus acidus ceremin sebagai indikator kolorimetri untuk alternatif analisis konsentrasi logam Hg secara citra digital. Bio NPP yang digunakan sebagai indikator kolorimetri logam Hg pada penelitian ini disintesis pada kondisi optimum.Kondisi optimum sintesis Bio NPP diperoleh pada perbandingan volume ekstrak buah Phyllanthus acidus ceremin dan AgNO 3 1 : 1 dan lama waktu penyinaran dengan cahaya matahari selama 1 jam. Bio NPP yang terbentuk diketahui selektif terhadap ion logam Hg(II) yang ditandai dengan berubahnya warna Bio NPP dari kuning kecoklatan menjadi bening. Selain itu Bio NPP yang telah disintesis pada penelitian ini dapat digunakan sebagai indikator kolorimetri analisis logam Hg meggunakan spektrofotometer UV-Vis dengan limit deteksi 7.56 ppb. Kata kunci : merkuri, buah ceremin, nanopartikel perak, indikator kolorimetri
[IMPLEMENTATION OF 2013 CURRICULUM FOR CHEMICAL TEACHERS IN SMA Negeri AT BENGKULU ] This researc... more [IMPLEMENTATION OF 2013 CURRICULUM FOR CHEMICAL TEACHERS IN SMA Negeri AT BENGKULU ] This research is a description research conducted from SMA Negeri 1 to SMA Negeri 10 Kota Bengkulu for chemistry teacher in 2016/2017 academic year. This study aims to describe the implementation of the 2013 curriculum for chemistry teachers in the SMA Negeri in Bengkulu City. The population of this research is all the chemistry teachers who teach in ten SMA Negeri in Bengkulu consisting of 42 teachers. Samples were taken by proportional random sampling technique as much as 20%, but the samples taken are teachers who have implemented the curriculum 2013. Obtained final sample of 26 teachers. In this study, a questionnaire was used to collect data, including indicators of the overall implementation of the curriculum, scattered on 53 points of statement, using Likert Scale with a score of 1 to 4. which was then processed using Statistical Product Service Solution(SPSS)16 program. The results showed that the implementation of the 2013 curriculum, the average percentage of teachers who have implemented is 66.67% with the category mostly implemented. Specifically that is, planning obtained at 65,385%, implementation obtained at 57,692%. and assessment of learning result obtained at 76,923% with category mostly executed.
[CONVERSION OF LIQUID WASTE OIL PALM OIL FACTORY BECOME BIOFUEL WITH MONi / HZ CATALYST] This stu... more [CONVERSION OF LIQUID WASTE OIL PALM OIL FACTORY BECOME BIOFUEL WITH MONi / HZ CATALYST] This study aims to produce biofuel from liquid waste oil PMKS with worditik cracking using catalystMoNi / HZ. This study involves the preparation of a catalyst performed by means of a separate impregnation, this impregnation lasting for 12 hours. The next stage of sample preparation includes heating, filtering, degumming, bleaching and ALB determination, followed by the production of methyl esters through esterification and transesterification processes. Then the obtained methyl ester was cracked using a catalyst for 2 hours at 380 °C and followed by distillation of the product for 2 hours at 380 °C, followed by distillation step at 380 °C to obtain methyl ester. The physical characteristics of biofuel resulting from the catalytic cracking reaction of the methyl ester using the MoNi / HZ catalyst of the PMKS wastewater include the acid number 1.92 mg KOH / g, density 0.803 g/cm 3 , kinematic viscosity 1,113 cSt, a pour poin of 0 o C and fog poin at 1,43 o C. Biofuel resulting from catalytic cracking using this MoNi / HZ catalyst of very high biofuel acid numbers can be used in areas that have a cold climate. the biofuel viscosity of the experimental results has not matched the viscosity of gasoline or kerosene, so it can not be used as fuel equivalent to gasoline and kerosene with the composition of 100% biofuel density from biofuel is still slightly above gasoline and kerosene Keyword : Biofuel, MoNi/HZ catalysts, PMKS liquid waste Abstrak Penelitian ini bertujuan untuk menghasilkan biofuel dari minyak limbah cair PMKS dengan perengkahan kataitik menggunakan katalis MoNi/HZ. Katalis yang digunakan disiapkan dengan cara mencampurkan zeolit alam (HZ) dengan .9 O melalui proses refluks pada suhu 90 o C selama 12 jam, disaring dan dikeringkan pada suhu 110 o C selama 3 jam dan selanjutnya diaktivasi dengan kalsinasi pada 500 o C menghasilkan katalis Ni-HZ. Proses impregnasi kedua , katalis Ni-HZ dicampurkan dengan (NH 4) 6 Mo 7 O 24 .4H 2 O , lalu direfluks pada suhu 90 o C selama 12 jam, disaring dan dikeringkan pada suhu 110 o C selama 3 jam dan selanjutnya diaktivasi dengan kalsinasi pada 500 o C menghasilkan katalis MoNi-HZ..Sampel limbah dipreparasi melalui tahapan pemanasan, penyaringan, degumming, bleaching dan penentuan ALB, dilanjutkan dengan pembuatan metil ester melalui proses esterifikasi dan transesterifikasi. Metil ester yang didapat direngkah menggunakan katalis MoNi-HZ selama 2 jam pada suhu 380 o C dan dilanjutkan dengan destilasi hasil selama 2 jam pada suhu 380 o C, untuk memperoleh metil ester. Karakteristik biofuel hasil perengkahan memiliki angka asam 1,92 mg KOH/g, densitas 0,803 g/cm 3 , viskositas kinematik 1,113 cSt, titik tuang 0 o C dan titik kabut 1,43 o C. Hasil penelitian menunjukkan bahwa karakteristik biofuel hasil dari perengkahan ini masih belum bisa digunakan secara langsung sebagai bahan bakar yang setara dengan bensin dan kerosin pada komposisi 100% biofuel. Kata Kunci : Biofuel, katalis MoNi/HZ, Metil Ester, limbah cair PMKS
[COMPARISON OF STUDENT LEARNING OUTCOMES BEETWEN INDEX CARD MATCH AND BAMBOO DANCING LEARNING MET... more [COMPARISON OF STUDENT LEARNING OUTCOMES BEETWEN INDEX CARD MATCH AND BAMBOO DANCING LEARNING METHOD] In the learning process teachers often use lecture methods so that students tend to only accept what is given by teachers and many students who feel chemistry lessons are difficult and confusing lessons. This results in low student learning outcomes. One effort that can be done by using the teacher method is varied, one of which is the method of Index Card Match and Bamboo Dancing. This research type is experiment. The population is all students in class X MIPA SMA Negeri 2 Kota Bengkulu as many as 216 students. The sample selection was done by homogeneity test with the result obtained by class X MIPA C (experimental class I) which applied Index Card Match method and X MIPA D (experiment II class) applying Bamboo Dancing method. Data analysis used is normality test, homogeneity test and t test. In this study the results of learning are seen the value of the difference between the average pretest and posttest, where obtained for class X MIPA C is 53.75 and class X MIPA D is 45.55. Then t test is obtained where t test t > t table (3,76 > 2,38), so it can be concluded that there is a significant difference between student learning result using Index Card Match method with Bamboo Dancing on chemical compound nomenclature material. Abstrak Dalam proses pembelajaran guru sering menggunakan metode ceramah sehingga siswa cenderung hanya menerima apa yang diberikan oleh guru dan banyak siswa yang merasa pelajaran kimia adalah pelajaran yang sulit dan membingungkan. Hal ini menyebabkan hasil belajar siswa rendah.Salah satu upaya yang dapat dilakukan guru yaitu dengan menggunakan metode yang bervariasi, salah satunya yaitu metode Index Card Match dan Bamboo Dancing. Jenis penelitian ini adalah eksperimen. Populasi adalah semua siswa di kelas X MIPA SMA Negeri 2 Kota Bengkulu sebanyak 216 siswa. Pemilihan sampel dilakukan dengan uji homogenitas dengan hasil didapatkan kelas X MIPA C (kelas eksperimen I) yang menerapkan metode Index Card Match dan X MIPA D (kelas eksperimen II) yang menerapkan metode Bamboo Dancing. Analisa data yang digunakan yaitu uji normalitas, uji homogenitas dan uji t. Pada penelitian ini hasil belajar yang dilihat yaitu nilai dari selisih rata-rata pretest dan posttest, dimana diperoleh untuk kelas X MIPA C yaitu 53.75 dan kelas X MIPA D yaitu 45.55. Kemudian dilakukan uji t dimana diperoleh t hitung > t tabel (3,76> 2,38), sehingga dapat disimpulkan bahwa terdapat perbedaan yang signifikan antara hasil belajar siswa yang menggunakan metode Index Card Match dengan Bamboo Dancing pada materi tata nama senyawa kimia.
[PHYTOCHEMICAL SCREENING AND ANTIOXIDANT ACTIVITY OF SOME FRACTIONS FROM BARK OF CASTOR (Ricinus ... more [PHYTOCHEMICAL SCREENING AND ANTIOXIDANT ACTIVITY OF SOME FRACTIONS FROM BARK OF CASTOR (Ricinus communis L.)]. The Phytochemical screening was conducted to determine secondary metabolites found in the bark of castor (Ricinus communis L.).The test results of phytochemical screening that has been done presence of phenolic, flavonoids, alkaloids, saponins, and terpenoids. Extraction is done by maceration using ethanol 96%. Tests performed on the fraction of the antioxidant activity of ethanol, ethyl acetate, n-hexane, and ascorbic acid as compared to using DPPH. The results of measuring the antioxidant activity using Uv-Vis Spectrophotometer IC 50 values obtained succession namely fraction of ethanol, ethyl acetate, n-hexane, and ascorbic acid, 33,38, 24,38, 289, 05 and 12, 48 ppm. Fraction of ethanol and ethyl acetate has a very strong antioxidant activity due IC 50 <50 ppm while the n-hexane fraction very weak antioxidant activity. Phenolic and flavonoids the bark of castor that can be potentially as antioxidants
[RELATIONS OF STUDENTS PERCEPTION AND VARIATION TEACHING STYLE WITH CHEMISTRY LEARNING OUTCOMES A... more [RELATIONS OF STUDENTS PERCEPTION AND VARIATION TEACHING STYLE WITH CHEMISTRY LEARNING OUTCOMES AT CLASS X MIPA IN SMA NEGERI KOTA BENGKULU IN 2016/2017 ACADEMICS YEAR ] In teaching and learning activities at school, often faced with the problem of low student learning outcomes. Student learning outcomes is one indicator to measure success in the implementation of learning process. Student learning outcomes are influenced by several factors, both external and internal factors. One of the internal factors that can affect student learning outcomes is perception. The object of perception here is the variation of the teacher's teaching style. The purpose of this study is to obtain data about students' perceptions about the variation of teaching style of chemistry teacher and student chemistry learning outcomes in SMA Negeri Kota Bengkulu academic year 2016/2017. Polpulation in this research is all students of class X of MIPA in State Senior High School of Bengkulu which amounted to 1620 students. The technique of determining the sample that will be used by the researcher is Proportional Random Sampling technique and the sample is 324 students. Data analysis used in this research is descriptive analysis, normality test, linearity, correlation and hypothesis test. Based on the analysis, the correlation coefficient value is 0.232 > 0.11 (r count t > r table), and t count > t table (4,312 > 1,967), indicating that there is a significant positive correlation between students' perception about teacher teaching style variation and student's chemistry learning result. Abstrak Pada kegiatan belajar mengajar disekolah, sering kali dihadapkan pada masalah rendahnya hasil belajar siswa. Hasil belajar siswa merupakan salah satu indikator untuk mengukur keberhasilan dalam pelaksanaan proses pembelajaran. Hasil belajar siswa dipengaruhi oleh beberapa faktor, baik faktor ekternal maupun faktor internal. Salah satu faktor internal yang dapat mempengaruhi hasil belajar siswa adalah persepsi. Yang menjadi objek dari persepsi disini adalah variasi gaya mengajar guru. Tujuan penelitian ini adalah untuk memperoleh data mengenai persepsi siswa tentang variasi gaya mengajar guru kimia dan data hasil belajar kimia siswa di SMA Negeri Kota Bengkulu tahun ajaran 2016/2017. Polpulasi dalam penelitian ini adalah seluruh siswa kelas X MIPA di SMA Negeri Kota Bengkulu yang berjumlah 1620 siswa. Teknik penentuan sampel yang akan digunakan peneliti yaitu teknik Proportional Random Sampling dan didapatkan sampel sebanyak 324 siswa. Analisis data yang digunakan pada penelitian ini adalah analisa deskriptif, uji normalitas, linieritas, korelasi dan uji hipotesis. Berdasarkan analisis diperoleh nilai koefisien korelasi 0,232>0,11 (r hitung > r tabel), dan nilai t hitung > t tabel (4,312>1,967), yang menunjukkan bahwa ada hubungan positif yang signifikan antara persepsi siswa tentang variasi gaya mengajar guru dengan hasil belajar kimia siswa.
Antioxidant agents play an important role in inhibiting free radical molecules activity thus prev... more Antioxidant agents play an important role in inhibiting free radical molecules activity thus preventing the cancer disease. This current study aimed to evaluate antioxidant and cytotoxicityproperties of ethyl acetate fractions of Pandanustectorius fruit extract on HeLa cell lines. The radical scavenging activity was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The cytotoxicity was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against human HeLa cell lines. The result showed that all ethyl acetate fractions of P. tectoriusfruit had high antioxidant property. All of seven fractions of the ethyl acetate extract were observed based on the IC 50 value and had high DPPH free radical scavenging activity with the IC 50 value range from 0.3 to 2.4 mg/ml compare to positive control,quercetin(IC 50 = 0.2 mg/ml). Based on the DPPH free radical scavenging activity (antioxidant property), three of seven fractions were chosen for the MTT assay to analyze their cytotoxic activity as anticancer potential agent against HeLa cell lines.From MTT result, one of tree fractions were showed cytotoxicity activity against HeLa cell lines with the IC 50 value is 12 µg/ml (less than 30 µg/ml), while anothertwo fractions was found not cytotoxic against HeLa cell lines.It is clearly indicated that P. tectoriusfruit has a very good potential as antioxidant and anticancer agent.
[RELATIONSHIP BETWEEN LABORATORY FACILITIES AND STUDENT PROCESS SKILLS AT CLASS XI MIPA 5 IN SMA ... more [RELATIONSHIP BETWEEN LABORATORY FACILITIES AND STUDENT PROCESS SKILLS AT CLASS XI MIPA 5 IN SMA NEGERI 3 KOTA BENGKULU] The purpose of this study was to determine the relationship of laboratory facilities to students' science process skills in the laboratory. This research is a correlational research. The population in this study is all students of class XI MIPA 5 academic year 2016/2017 in SMA Negeri 3 Kota Bengkulu. This research uses total sampling technique so that the entire population is used as research sample. The independent variable (x) in this research is chemical laboratory equipment and dependent variable (y) is the science process skill of students in laboratory of SMA Negeri 3 Kota Bengkulu.. Data collection in this research using questionnaire instrument with 30 items and observation sheet with 15 items. Technique of data analysis using expert validity test, questionnaire analysis, observation analysis of science process skill, normality test, linearity test, correlation analysis and hypothesis test. Data analysis using the help of SPSS 16 program. The results of data processing correlation coefficient (r) obtained that is equal to 0.387 at 5% significance level.. The result of hypothesis test shows that Ha is accepted which means there is a significant correlation between laboratory facilities and science process skill of students in laboratory on chemistry learning of students of class XI MIPA 5 SMA Negeri 3 Kota Bengkulu academic year 2016/2017 Abstrak Tujuan penelitian ini adalah untuk mengetahui hubungan sarana laboratorium terhadap keterampilan proses sains siswa di laboratorium. Penelitian ini merupakan penelitian korelasional. Populasi pada penelitian ini adalah seluruh siswa-siswi kelas XI MIPA 5 tahun ajaran 2016/2017 di SMA Negeri 3 Kota Bengkulu. Penelitian ini menggunakan teknik total sampling sehingga seluruh populasi digunakan sebagai sampel penelitian. Variabel bebas (x) pada penelitian ini adalah sarana laboratorium kimia dan variabel terikat (y) adalah keterampilan proses sains siswa di laboratorium SMA Negeri 3 Kota Bengkulu.Teknik pengumpulan data pada penelitian ini menggunakan instrument angket dengan 30 butir pertanyaan dan lembar observasi dengan 15 butir pertanyaan.. Teknik analisis datanya menggunakan uji validitas ahli, analisis angket, analisis observasi keterampilan proses sains, uji normalitas, uji linearitas, analisis korelasi dan uji hipotesis. Analisis data menggunakan bantuan program SPSS 16. Hasil dari pengolahan data koefisien korelasi (r) yang diperoleh yaitu sebesar 0,387 pada taraf signifikansi 5%.. Hasil uji hipotesis yang diperoleh menunjukkan bahwa H a diterima yang artinya terdapat hubungan yang signifikan antara sarana laboratorium dan keterampilan proses sains siswa di Laboratorium pada pembelajaran kimia siswa-siswi kelas XI MIPA 5 SMA Negeri 3 Kota Bengkulu tahun ajaran 2016/2017 .
[ANALYSIS OF SILICA ADSORPTION CAPACITY FROM THE SAND OF PANTAI PANJANG BENGKULU AGAINST RHODAMIN... more [ANALYSIS OF SILICA ADSORPTION CAPACITY FROM THE SAND OF PANTAI PANJANG BENGKULU AGAINST RHODAMINE B DYES ] This research was aimed to study the adsorption capacity of synthetic silica on Rhodamine B dyes. Synthetic silica was obtained from the sand of Pantai Panjang Bengkulu by alkali fusion method using KOH at 360 °C for 4 hours in furnace to obtain potassium silicate crystals (K 2 SiO 3). The crystals were then added 500 mL aqua DM, stirred and sterilized for 24 hours folloed by filtered. The filtrate was dropped with 10 M HCl solution until the pH of filtrate solution reached at 1 to 2 and formed a silent white gel for 24 hours. Moreover, the gel was filtered with filter paper and washed with aqua DM until pH is neutral and free from KCl, and dried in an oven at 60 °C for 18 hours. The obtained silica powder is then smoothed with mortar and weighed. The adsorbent of Rhodamine B dyes using the synthetic silica powder was performed on pH variation at 2, 3, 4, 5, 6, and 7 , and variation of contact time at 10, 20, 30, 40, 50, and 60 min. The results showed that the optimum condition of adsorption of Rhodamine B by silica from Pantai Panjang sand occured at optimum pH 2 and optimum contact time 20 minutes; with adsorption capacity of 4.95 mg / g and 4.79 mg/g; and with adsorption efficiency of 99.00% and 95.89%. Abstrak Penelitiaan ini bertujuan untuk mempelajari kapasitas adsorpsi silika pada Rhodamin B. Sintesis silika diperoleh dari pasir Pantai Panjang Bengkulu dengan metode alkali fusion menggunakan KOH dalam furnace bersuhu 360°C selama 4 jam, untuk memperoleh kristal kalium silikat (K 2 SiO 3).. Kristal kemudian ditambahkan aquademin sebanyak 500 ml , diaduk, dan didiamkan selama 24 jam, disaring dan filtrat ditetesi dengan larutan HCl 10 M hingga pH filtrate mencapai pH 1 hingga 2 dan terbentuk gel putih yang didiamkan selama 24 jam, selanjutnya gel disaring dengan kertas saring dan dicuci dengan aquademin hingga pH netral dan bebas dari KCl, dikeringkan dalam oven pada suhu 60 °C selama 18 jam. Serbuk silika yang diperoleh selanjutnya dihaluskan dengan mortar dan ditimbang. Adsorpsi Rhodamin B menggunakan silika hasil sintesis dilakukan pada variasi pH 2, 3, 4, 5, 6, dan 7 dengan variasi waktu kontak 10, 20, 30, 40, 50, dan 60 menit. Hasil penelitian menunjukkan bahwa kondisi optimum adsorpsi Rhodamin B oleh silika dari pasir Pantai Panjang dengan pH optimum terjadi pada pH 2 dan waktu kontak optimum 20 menit; dengan kapasitas adsorpsi sebesar 4,95 mg/g dan 4,79 mg/g; dan dengan efisiensi adsorpsi sebesar 99,00 % dan 95,89 %.
[COMPARISON OF STUDENTS LEARNING RESULT USING MEDIA Daily Chem Quiz AND GAMES Ranking One Chemist... more [COMPARISON OF STUDENTS LEARNING RESULT USING MEDIA Daily Chem Quiz AND GAMES Ranking One Chemistry Quiz] The aim of this research is to know the difference of students' chemistry learning result using Daily Chem Quiz (DC Quiz) and Ranking One Chemistry Quiz (ROC Quiz) media at class X MIPA in SMA Negeri 1 Bengkulu Tengah 2016 / 2017 academic year. This research is quasi research experiment. The independent variables are DC Quiz and ROC Quiz media, the dependent variable is the students' learning result and the control variable is the Think-Pair-Share (TPS) cooperative learning methods. The population is all students of class X MIPA at 2016/2017 academic year consisting of 4 classes, and to determine the sample is done by homogeneity test then taken by simple random sampling. The selected sample is the class X MIPA 3 as experiment class I using DC Quiz and class X MIPA 1 as experimental class II using RC Quiz. Data analysis used were mean score, normality test, homogeneity test, and t test. Based on posttest value of both class, it is known that the average value of posttest at experiment class I is 78.79 and at experiment class II is 84,77. The result of data analysis shows that the data is normally distributed and has homogeneous variance and obtained t count> t tabel (2,47> 2,39). The results of this study indicate that H 0 rejected and H a accepted in other words there is a significant difference between student learning outcomes using DC Quiz media and RC Quiz media. Abstrak Penelitian ini bertujuan untuk mengetahui perbedaan hasil belajar kimia siswa menggunakan media Daily Chem Quiz (DC Quiz) dan Ranking One Chemistry Quiz, (ROC Quiz) pada kelas X MIPA di SMA Negeri 1 Bengkulu Tengah Tahun ajaran 2016/2017.Penelitian ini merupakan penelitian kuasi eksperimen. Variabel bebas pada penelitian ini adalah media DC Quiz dan media ROC Quiz, variabel terikat adalah hasil belajar kimia siswa dan variable kontrol yaitu pembelajaran kooperatif tipe Think-Pair-Share (TPS). Populasi dalam penelitian ini yaitu siswa kelas X MIPA tahun pelajaran 2016/2017 yang terdiri dari 4 kelas, dan untuk menentukan sampel dilakukan uji homogenitas yang kemudian diambil secara simple random sampling. Sampel yang terpilih yaitu siswa kelas X MIPA 3 sebagai kelas eksperimen I menggunakan media DCQ dan X MIPA 1 sebagai kelas eksperimen II menggunakan media RCQ. Analisa data yang digunakan adalah nilai rata-rata, uji normalitas, uji homogenitas, dan uji t. Berdasarkan nilai posttest kedua kelas eksperimen, diketahui nilai rata-rata posttest kelas eksperimen I adalah 78,79 sedangkan untuk kelas eksperimen II adalah 84,77. Hasil analisis data menunjukkan bahwa data berdistribusi normal dan memiliki varians yang homogen serta diperoleh t hitung > t tabel (2,47 > 2,39). Hasil penelitian ini menunjukkan bahwa H 0 ditolak dan H a diterima dengan kata lain terdapat perbedaan yang signifikan antara hasil belajar siswa yang menggunakan media DCQ dan RCQ..
[DETERMINATION OF ETHYL ACETATE FRACTION FROM Peronema canescens LEAF EXTRACT AGAINST Plasmodium ... more [DETERMINATION OF ETHYL ACETATE FRACTION FROM Peronema canescens LEAF EXTRACT AGAINST Plasmodium berghei INFECTED Mus musculus] This study was conducted to identify secondary metabolite compounds contained in ethanol extract and ethyl acetate fraction from Peronema canescens leaf (sungkai) and to measure the effect of ethyl acetate fraction on anti plasmodium activity on Mus musculus infected by Plasmodium berghei. The ethyl acetate extract was obtained by maceration of leaves with 96% ethanol solution in3 days followed by fractionation by ethyl acetate for further test. 25 of male white M. musculus with the weight 20-40 g and 6-8 weeks old , divided into 5 groups with 5 head / group. Groups 3, 4 and 5 are treated and groups 1 and 2 are controls. The negative control will be given food and drink only, and for positive control group will be given chloroquine with dose 0,028, 0,056, and 0,084 g / KgBW. Development of levels of parasitemia were calculated by by observing a thin blood smear with giemsa staining under a microscope , observed until the parasitemia in the blood had reached 20-30% to be given a 3-day follow-up treatment, and then for the next 7 days after it was given treatment.. Anti-plasmodium activity test is determined by the number of parasitemia, percent growth and resistance of parasitemia in the blood. Data were analyzed by using one way anova method (α = 0,05 and 0,01). The results showed that the secondary metabolite compounds found in the ethyl acetate fraction of P.canescens leaf, namely alkaloids, flavonoids, tannins and phenolics and at a dose of 0.056 g / KgBW ethyl acetate fraction can inhibit the growth of parasitemia in the blood of M. musculus by 50 , 89% , with greater percentage of parasitemic inhibition compared with positive and negative control group. Abstrak Penelitian ini dilakukan untuk mengidentifikasi senyawa metabolit sekunder yang terdapat dalam ekstrak etanol dan fraksi etil asetat dari daun Peronema canescens (sungkai) serta untuk mengukur pengaruh pemberian fraksi etil asetat terhadap aktivitas anti plasmodium pada Mus musculus (mencit) jantan yang terinfeksi Plasmodium berghei. Ekstrak diperoleh dari hasil maserasi daun P.canescens dengan etanol 96% selama 3 hari, dilanjutkan dengan fraksinasi dengan etil asetat daun P.canescens Sebanyak 25 ekor M. Musculus putih jantan dengan berat badan 20-40 g dan berumur 6-8 minggu , dibagi menjadi 5 kelompok masing masing 5 ekor/ kelompok. Kelompok 3, 4 dan 5 merupakan kelompok perlakuan dan kelompok 1 dan 2 merupakan kelompok kontrol. Untuk kelompok perlakuan kontrol negatif hanya akan diberikan pakan dan minum saja , untuk kelompok kontrol positif akan diberikan klorokuin dengan dosis 0,028, 0,056 dan 0,084 g/KgBB. Tingkat perkembangan parasitemia dihitung dari pengamatan apusan darah M.musculus dengan pewarnaan giemsa dibawah mikroskop. Bila parasitemia dalam darah telah mencapai 20-30% , diberikan perlakuan lanjut selama 3 hari, dan kemudian dihitung untuk 7 hari berikutnya. Uji aktifitas anti plasmodium ditentukan oleh jumlah parasitemia, persen pertumbuhan dan hambatan parasitemia dalam darah. Data dianalisis dengan menggunakan metode one way anova (α=0,05 dan 0,01). Hasil penelitian menunjukkan bahwa senyawa metabolit sekunder yang terdapat pada fraksi etil asetat daun P.canescens yaitu alkaloid, flavonoid, tanin dan fenolik serta pada dosis 0,056 g/KgBB fraksi etil asetat P. canescens dapat menghambat pertumbuhan parasitemia sebesar 50,89%., dimana lebih besar persentase penghambatannya dibandingkan terhadap kelompok kontrol positif dan negatif.
[COMPARISON STUDY OF COOPERATIVE LEARNING USING CHEMICAL DOMINO CARD AND FLASH CARD MEDIA] This s... more [COMPARISON STUDY OF COOPERATIVE LEARNING USING CHEMICAL DOMINO CARD AND FLASH CARD MEDIA] This study aims to measure differences in the results of chemistry learning between experimental class 1 classes that apply Chemical Domino Card learning media with experimental class 2 that apply Flash Card media at nomenclature of chemical compounds topics in class X IPA SMA Negeri 2 Kota Bengkulu at 2016 / 2017 academic year. Use of these two learning media is considered from the practicality, advantages, and effectivenes The type of research is a quasi experimental research with the population of all students of class X MIPA in SMA Negeri 2 Kota Bengkulu at 2016/2017 academic year , which a sample class is X MIPA E and X MIPA F. Implementation of research conducted by using two experimental class, X MIPA E which uses Chemical Domino Card media and class X MIPA F using Flash Card media. Data analysis used are mean value, homogeneity test, normality test and t test. The average value of posttest experimental class I for first and second meeting is 77,5 and 79,72, while for experiment class II is 86,94 and 88,61. Then t test is done by using difference of pretest and posttest value of student, which is obtained that both at first meeting and second t count> t table that is 2,44> 2,38081 (first meeting) and 2,81> 2,38081 (second meeting). The results of this study indicate that there is a significant difference of student learning outcomes using Chemical Domino Card and Flash Card media on the nomenclature of chemical compounds. Abstrak Penelitian ini bertujuan untuk mengukur perbedaan hasil belajar kimia antara kelas kelas eksperimen 1 yang menerapkan media pembelajaran Chemical Domino Card dengan kelas eksperimen 2 yang menerapkan media pembelajaran Flash Card pada materi materi tata nama senyawa kimia di kelas X IPA di SMA Negeri 2 Kota Bengkulu tahun ajaran 2016/2017.Penggunaan kedua media pembelajaran ini dipertimbangkan dari kepraktisan, kelebihan, dan efektif untuk dilakukan. Jenis penelitian yang digunakan adalah penelitian kuasi eksperimen dengan populasi seluruh siswa kelas X MIPA di SMA N 2 Kota Bengkulu tahun ajaran 2016/2017 dan sampel penelitian adalah kelas X MIPA E dan kelas X MIPA F. Pelaksanaan penelitian dilakukan menggunakan dua kelas eksperimen, yaitu kelas X MIPA E menggunakan media Chemical Domino Card dan kelas X MIPA F menggunakan media Flash Card. Analisa data yang digunakan adalah nilai rata-rata, uji homogenitas, uji normalitas dan uji t. Nilai rata-rata postest kelas eksperimen I untuk pertemuan pertama dan kedua adalah 77,5 dan 79,72, sedangkan untuk kelas eksperimen II adalah 86,94 dan 88,61. Kemudian dilakukan uji t dengan menggunakan selisih nilai pretest dan postest siswa, yang mana diperoleh bahwa baik pada pertemuan pertama dan kedua t hitung >t tabel yaitu adalah 2,44>2,38081 (pertemuan pertama) dan 2,81>2,38081 (pertemuan kedua). Hasil penelitian ini menunjukkan bahwa terdapat perbedaan yang signifikan dari hasil belajar siswa yang menggunakan media Chemical Domino Card dan Flash Card pada materi tata nama senyawa kimia.
[ANTIOXIDANT ACTIVITY OF SECONDARY METABOLITE FROM ENDOFIT BACTERIA OF Moringa oleifera L (KELOR)... more [ANTIOXIDANT ACTIVITY OF SECONDARY METABOLITE FROM ENDOFIT BACTERIA OF Moringa oleifera L (KELOR) ROOTS] The purpose of this research was aims to isolate and measure the ability of antioxidant activity from secondary metabolites produced by endophytic bacteria that grow in the live tissue root of Moringa oleifera L. (kelor). Endophytic bacteria were purified and cultured using a solid Murashige-skoog (MS) medium for 3 days at room temperature. Secondary metabolites were obtained by centrifugation process at a rate of 3000 rpm for 20 minutes. The bacterial fermentation process using Nutrient Broth (NB) medium for 72 hours with a shaker speed at 170 rpm. The suspension supernatant was extracted with a maceration method using 86% ethyl acetate, followed by vacuum rotary evaporator concentration at 40 ° C. The extract antioxidant activity test was performed using the DPPH (1,1-diphenyl-2-picrylhydrazyl) method using a UV-Vis spectrophotometer at 517 nm wavelength and ascorbic acid as standard. The result of DPPH test showed that the antioxidant activity of ethyl acetate extract of endophytic bacterial from root of M. oleifera L root has IC 50 value at 315, 396 ppm. Based on these results, it can be concluded that the secondary metabolite extract of endophytic bacterial from M. oleifera L root classified as weak antioxidant (IC50> 250 ppm). Abstrak Penelitian ini bertujuan untuk mengisolasi dan mengukur kemampuan aktivitas anti oksidan dari metabolit sekunder yang dihasilkan oleh bakteri endofit yang tumbuh di dalam jaringan hidup a kar Moringa oleifera L.(kelor). Bakteri endofit dimurnikan dan dibiakkan menggunakan medium padat Murashige-skoog (MS) selama 3 hari pada suhu ruang. Metabolit sekunder didapatkan melalui proses sentrifugasi dengan kecepatan 3000 rpm selama 20 menit.dari suspensi hasil proses fermentasi bakteri menggunakan medium Nutrient Broth (NB) selama 72 jam dengan kecepatan shaker 170 rpm. Supernatan yang didapatkan selanjutnya diekstraksi dengan metode maserasi menggunakan etil asetat 86 %, , dilanjutkan pemekatan dengan vacuum rotary evaporator pada suhu 40 o C. Uji aktivitas antioksidan ekstrak dilakukan dengan menggunakan metode DPPH (1,1-difenil-2-pikrilhidrazil) menggunakan spektrofotometer UV-Vis pada panjang gelombang 517 nm dan asam askorbat sebagai standar. Hasil u j i D P P H menunjukkan bahwa aktivitas antioksidan ekstrak etil asetat bakteri endofit akar M. oleifera L memiliki nilai IC50 sebesar 315, 396 ppm. Ber dasarkan has il t er sebut , dapat dis i mpu lkan ba hwa ekst r ak met abo lit sekunder bakt er i endo fit akar M. oleifera L t er go lo ng a nt io ksida n le ma h (I C 50 > 250 ppm). Kata kunci : Antioksidan, bakteri endofit, Moringa oleifera L. Kelor.
The problem of environmental polution caused by waste of batik industry lately is increasing, so ... more The problem of environmental polution caused by waste of batik industry lately is increasing, so it needed a method to overcome that problem. The aim of this study was to determine the ability of activated charcoal from coconut fiber palm in adsorbing Reactive Red-120 and Direct Green-26 dyes in waste of batik along with determining the parameters of isotherms adsorption using UV-Vis Spectrophotometer analysis method. Variations of pH, contact time, adsorbent weight and temperature were carried out as variable to obtain optimum conditions of the adsorption process. The optimum of conditions for Reactive Red-120 occured at pH 3 and a contact time of 30 minutes, while Direct Green-26 occurred at pH 4 and a contact time of 40 minutes, with each adsorbent weight 150 mg and the temperature 30°C. Adsorption isotherms determined by Freundlich and Langmuir models with maximum adsorption capacity (Qmax) were obtained for the Reactive Red-120 was 400 mg/g, while Direct Green-26 is 169 mg/g.
The purpose of this research is to know the difference of students' chemistry learning result bet... more The purpose of this research is to know the difference of students' chemistry learning result between experiment 1 class which applied learning cycle model (5E) with experiment 2 class that apply two stay two stray learning model on acid acid base material in class XI IPA in SMA Plus Negeri 7 Bengkulu City. Research conducted is a research with the type of quasi experiment. Chemical learning result data obtained from pretest value and posttest value where the average value of improvement of cognitive learning result for experiment class 1 is 47,78. And the average value of cognitive learning improvement for experiment class 2 is 54.875. With testing the hypothesis using t test with significant level (α = 0,01), then got value for titung equal to 2,60 and for ttable got value equal to 2,380. The results showed that there were significant differences in learning outcomes between classes that applied learning cycle model (5E) with classes that applied the two stay two stray learning model.
This study aims to determine the antioxidant activity of jarak kepyar’s leaf extracts (Ricinus c... more This study aims to determine the antioxidant activity of jarak kepyar’s leaf extracts (Ricinus communis L.) and to determine of the fraction the growth of Erwinia carotovora. Jarak kepyar’s leaf extracted by maceration method using ethanol and fractionated using n-hexane and ethyl acetate. Antioxidant test using DPPH (1,1-diphenyl-2-picrylhydrazyl) with various concentrations of 125 ppm, 100 ppm, 75 ppm, 50 ppm, 25 ppm, 15 ppm and 5 ppm. Antibacterial test conducted on the active fractions as antioxidants using paper disc method and variations in the concentration of 1000 ppm, 500 ppm, 250 ppm, 125 ppm, 62.5 ppm. Phytochemical test results jarak kepyar’s leaf contain secondary metabolites are alkaloids, flavonoids, phenols and terpenoids. The test results demonstrate the antioxidant activity of ethyl acetate fraction is very strong as an antioxidant with IC50 values of 5.4 ppm and a strong ethanol fraction categorized as antioxidants IC50 of 99.8 ppm. Antibacterial test results showed inhibition of the leaf fraction of jarak kepyar’s (Ricinus communis L.) against Erwinia carotovora categorized weak growth in ethanol fractions with inhibition zone diameter of 4 mm and being in ethyl acetate fraction with a diameter of 5 mm.
The average students' chemical learning outcomes are still low, the low learning outcome is influ... more The average students' chemical learning outcomes are still low, the low learning outcome is influenced by several factors, including students still consider that chemistry as one of the scary, difficult to understand and less interesting lessons. Therefore, the research wants to vary the learning process in the classroom by applying the learning model of Discovery Learning with Group Investigation model. This research was aimed to find out the students’ achievement differences of chemical subject by using Discovery learning and Group Investigation model. The research is quasi experimental research. The population of this research were class X MIPA in SMAN 9 Bengkulu City, and the sample were X MIPA 2 and MIPA 3. This research using two experimental classes, that is class X MIPA 2 applying Group Investigation model and X MIPA 3 applying Discovery Learning model. Analysis of the data used is mean values, normality test, homogeneity test, and t-test. Post-test mean values for first experiment class is 78,12, but for second experiment class is 81,3. To determine whether the differences of student’s learning outcomes between both of experiment classes or not, we use t-test by using the differences between student’s pretest and posttest values, tcount > ttable (2,17 > 1,67). The result of this research showed that Ha accepted, in other words is a significant differences in learning outcomes of student’s applying Discovery Learning and Group Investigation model.
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